YUkon RIvers and Permafrost

High-latitude regions are affected by air temperatures rising well above the global average. Current atmospheric warming is causing permafrost to degrade, leading to changes in the water cycle at watershed scale. In addition, the effects of hydrological change are reinforced by rising river water temperatures. The main consequences regarding the intensity of erosive processes on river bed, and thus fluvial dynamics, remain unclear: the few studies conducted on this subject have led to divergent conclusions.
The aim of this project is to analyse the morphodynamic and sedimentary responses of a subarctic river, the Beaver Creek (Yukon Basin, Canada), to contemporary climate change. The Beaver Creek River drains a watershed characterized by two types of permafrost: one formed during the Pleistocene and the other during the Holocene. Undisturbed by direct anthropogenic development (i.e. dams, embankments, etc.), the Beaver Creek River will enhance the knowledge of the impact of climate change on the morphodynamic functioning of rivers in permafrost arctic environments, which is still poorly documented. Using an instrumented site, we aim to quantify potential bank erosion as a function of permafrost presence and characteristics (age, temperature, ice content, sediment composition, etc.), river discharge and water temperature. This will enable us to assess the impact of permafrost degradation on the sedimentary and morphological dynamics (mobility of fluvial forms) of the river.